Russia is now a "far greater threat" to the UK's national security than the Islamic State group, the head of the British army has said, according to the BBC.

In an interview with the Daily Telegraph, General Mark Carleton-Smith said Britain "cannot be complacent about the threat Russia poses".

"The Russians seek to exploit vulnerability and weakness wherever they detect it," he said.

The UK blames Russia for the Salisbury poisoning and several cyber-attacks.

In March, former Russian spy Sergei Skripal - who sold secrets to MI6 - and his daughter Yulia survived being poisoned with Novichok.

Dawn Sturgess, 44, was later exposed to the same nerve agent and died in hospital.

And in October, the UK government accused Russia's GRU military intelligence service of being behind four high-profile cyber-attacks on targets including the US Democratic Party and a small TV network in Britain.

Russia denies any involvement in the Skripal poisoning and has described cyber-attack accusations as a "rich fantasy".